Description: G. achirasense
is a (usually) solitary
geophytic cactus.Stem: Flattened or
globular, grey-green to olive green, 5-6 cm in diameter, up to 5 cm
tall, but in cultivation it can become 7-8 cm high (or more)
over the
years.Ribs: 12-15Radial spines: Stout 10 up to 12, but usually less in young
plants, bent against the body. Central spines: Usually absent, or 1 erected
one.Flowers: Are some of the largest in this genus, often growing
larger than the plant!, 6 up to 7 cm long and wide, dark to light
purple, with a darker
mid-strip.Fruit: Green Seeds: Dark brown.

Cultivation: It
is a summer grower species that offers no cultivation difficulties.
Water regularly in summer (but do not overwater ) Keep this plant almost dry in winter at a minimum
temperature of 0°C, prefer relatively rich substrate and
low pH
compost (if possible not limestone) otherwise
growth will stop altogether. Feed with a high
potassium fertilizer in summer. It is quite frost resistant if kept dry
(hardy to -5° C)
Sun Exposure: Light shade. It may tolerate
bright situations but is
likely to suffer from sun scorch or stunted growth if over exposed to
direct sunlight
during the hottest part of the day in summer. This plant needs plenty of space for
its roots, repotting should be done every other year or when the
it has outgrown its pot. This species is particularly
easy and accommodating, seldom suffer of
cryptogamic diseases.

Photo of of
plants belonging to theGymnocalycium
monvillei
complex(This
Taxonhas lots of
synonyms (like many other
gymnocalycium) whit several controversial
varieties and subspecies and comprises a multitude of different
forms, but where each form is linked to others by populations of plants
with intermediate